Abstract The Institute of Medicine has identified the prevention of birth defects as one of six priorities for the nation's health1 because annually, 150,000 infants (3% of all U.S. births) are born with some form of physical or mental birth defect.2 While the causes of most birth defects remain unknown, certain medications are known to increase rates of birth defects. For example, isotretinoin has been identified as a particularly teratogenic medication.3 Despite the resources that have been invested in the iPledge program, it has not been able to significantly reduce rates of adverse pregnancy outcomes related to the use of isotretinoin.5 We therefore propose to develop and then rigorously evaluate new educational materials which can be used to inform women about the most effective ways to prevent birth defects caused by the use of certain medications. Specifically, we will (1) develop a package insert that provides clear recommendations regarding use of highly effective contraception in order to avoid medication-induced birth defects, and (2) evaluate the effect of the new package insert on women's contraceptive choices while using isotretinoin. Our hypothesis is that the new package insert and educational materials will significantly increase the proportion of women who use highly effective contraception while taking isotretinoin.